Support grows for Baltimore protests as demonstrations spread across the U.S.

From coast to coast, marchers are taking to the streets to support Baltimore protesters and complain about police brutality in their own towns.

The momentum only seems to be building as the week goes on.

Demonstrations are planned for Thursday in Cincinnati, CNN affiliate WXIX reported. And Philly.com said a \"Philly is Baltimore\" protest will be held at Philadelphia City Hall.

Seattle, Portland, Oregon, and Oakland, California are on tap for Friday, which is also May Day or International Workers Day -- often used to call attention to issues affecting the working class and minorities.

In addition to Baltimore, protests took place in at least half a dozen cities Wednesday.

New York

Several hundred people streamed into Union Square for an \"NYC Rise Up & Shut It Down With Baltimore\" rally Wednesday night. Protesters were met by New York police officers who pushed them back.

A small scuffle broke out between the two front lines and police placed at least 20 people in zip ties in the street. The NYPD also handed out fliers and used loudspeakers to tell protesters and pedestrians to stay on the sidewalk.

One person was placed in an ambulance and taken away. The crowd headed toward Times Square.

The New York Police Department told CNN that more than 100 people were arrested during the demonstrations.

The rally was organized through social media, much like protests over the killing of Eric Garner, who died while police held him in what appeared to be a chokehold. The demonstrators chanted \"Black Lives Matter\" and \"Justice for Freddie Gray\" -- the Baltimore man whose death sparked street confrontations in Baltimore.

CNN affiliate WCBS reported Mayor Bill de Blasio sent a message to the protesters: \"I'd say that if you want to make change, keep things peaceful.\" A smaller rally was held Tuesday in New York.

Washington

In the nation's capital, about 500 protesters, mostly in their 20s, gathered and chanted, \"All night, all day, we're gonna fight for Freddie Gray.\"

The mood seemed more festive than confrontational, with songs by Public Enemy like \"Fight the Power\" playing and sign-language interpreters translating the music and chants.

The protest moved to the White House where most of the crowd dispersed. It started after most office workers had headed home and didn't disrupt the Washington workforce badly.

One of the groups involved in the protest is the DC Ferguson Movement. Organizer Eugene Puryear said the march was called to show solidarity with the residents in Baltimore and to highlight that police brutality is a national issue.

Minneapolis and Denver

Several hundred people gathered in Gold Medal Park in Minneapolis for a rally organized by the group of #BlackLivesMatter. The Minneapolis group held similar events in the past in response to alleged police brutality across the country.

In Denver, marchers took to the streets in the city's downtown area.

There was a minor scuffle and 11 arrests, according to police. Their charges included assault of a police officer, robbery, resisting police, disobedience to lawful orders, obstructing roadways and interference.

Protests also were held in Boston and Houston.

Ferguson

On Tuesday, violent protests took place in Ferguson, Missouri, where three people were shot, the city police reported.

Police said they didn't do the shooting. A 20-year-old man was arrested and the three victims were in stable condition -- two with wounds to the neck, one in the leg, police said.

Police said about 300 people marched, with protesters throwing rocks at police, damaging four police cars and setting trash and debris on fire near Northwinds Estates and West Florissant.

Chicago

In the Windy City, hundreds of protesters marched Tuesday from police headquarters at 35th and Michigan through the Southside, CNN affiliate WGN reported. Police made one arrest, for reckless conduct.

WGN said protesters spoke about police violence and the death of Rekia Boyd, who was killed by an off-duty officer in 2012. That officer was acquitted last week.